System for allocating data in a communications system and method thereof

• US 7,596,127 B1
• Filed: 10/31/2001
• Issued: 09/29/2009
• Est. Priority Date: 10/31/2001
• Status: Active Grant

• Current Assignee: Rovi Guides, Inc. (Adeia Inc.)
• Original Assignee: VIXS Systems Incorporated (Pixelworks Incorporated)
• Inventors: May, Michael R., Cave, Michael D.
• Primary Examiner(s): Yao, Kwang B
• Assistant Examiner(s): NGO, NGUYEN HOANG
• Application Number:
  US09/999,593
• Time in Patent Office: 2,890 Days
• Field of Search: 370/329, 370/330, 370/343, 370/344, 370/468, 370/260, 375/260
• US Class Current: 370/343
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling

Abstract

Poor transmission reliability is identified in a data channel. Multiple frequency carriers are used to transmit different sets of data within the data channel. A frequency bin is assigned to each frequency carrier. The frequency bins are used to provide data to each frequency carrier. A transmission power assigned to each frequency carrier may be insufficient to overcome noise in the data channel when all the frequency bins are used to transfer data concurrently. The number of frequency bins associated with frequency carriers of the data channel are reduced. Power is increased to the available frequency bins to improve transmission reliability. The available frequency bins are allocated across the data channel according to a pattern used to spread allocated transmission power across the data channel. The frequency bin pattern is rotated among available frequency bins of the data channel, allowing different frequency bins to be used for each transmission. Accordingly, a power spectral density associated with the transmissions remains within a nominal power spectral density.

Claims

1. A method comprising:

performing, for a first duration, a first wireless transmission of data via a first set of frequency bins of a plurality of frequency bins associated with a bandwidth of a channel, the first wireless transmission having a transmission power for at least one frequency bin of the first set of frequency bins that exceeds a predetermined nominal power spectral density;

performing, for a second duration separate from the first duration, a second wireless transmission of data via a second set of frequency bins of the plurality of frequency bins, the second set separate from the first set, the second wireless transmission having a transmission power for at least one frequency bin of the second set of frequency bins that exceeds the predetermined nominal power spectral density, wherein the second set of frequency bins is unused during the first duration and the first set of frequency bins is unused during the second duration; and

a collective power spectral density for the bandwidth averaged over the sum of the first duration and the second duration is not greater than the predetermined nominal power spectral density.

2. The method of claim 1, wherein the first set comprises even frequency bins of the plurality of frequency bins and the second set comprises odd bins of the plurality of frequency bins.

3. The method of claim 1, wherein the nominal power spectral density is associated with a power used to support all of the plurality of frequency bins.

4. The method of claim 1, further comprising:

determining the predetermined nominal power spectral density based on a transmission standard.

5. The method of claim 1, further comprising:

performing, for a third duration subsequent to the second duration, a third wireless transmission of data via a third set of frequency bins of the plurality of frequency bins, the third set separate from the first set and the second set, the third wireless transmission having a transmission power for at least one frequency bin of the third set of frequency bins that exceeds the predetermined nominal power spectral density; and

a collective power spectral density for the bandwidth averaged over the sum of the first duration, the second duration, and the third duration is not greater than the predetermined nominal power spectral density over the bandwidth.

6. The method of claim 1, further comprising:

performing, for a third duration subsequent to the second duration, a third wireless transmission of data via the first set of frequency bins, the third wireless transmission having a transmission power for at least one frequency bin of the first set of frequency bins that exceeds the predetermined nominal power spectral density; and

a collective power spectral density for the bandwidth averaged over the sum of the first duration, the second duration, and the third duration is not greater than the predetermined nominal power spectral density over the bandwidth.

7. The method of claim 6, further comprising:

performing, for a fourth duration subsequent to the third duration, a fourth wireless transmission of data via the second set of frequency bins, the fourth wireless transmission having a transmission power for at least one frequency bin of the second set of frequency bins that exceeds the predetermined nominal power spectral density; and

a collective power spectral density for the bandwidth averaged over the sum of the first duration, the second duration, the third duration, and the fourth duration is not greater than the predetermined nominal power spectral density over the bandwidth.

8. The method of claim 1, wherein the first set and the second set each is distributed substantially evenly across the bandwidth.

9. The method of claim 1, wherein performing the first wireless transmission and performing the second wireless transmission comprise performing the first wireless transmission and performing the second wireless transmission in response to determining an unsuitability of wireless transmissions via the first set of frequency bins.

10. The method of claim 9, further comprising determining the unsuitability of wireless transmissions via the first set of frequency bins based on one selected from a group consisting of:

a signal-to-noise ratio;

a bit error rate;

an amount of data transmissible via the channel; and

a receipt of a retransmission request.

11. A system comprising:

means for performing, for a first duration, a first wireless transmission of data via a first set of frequency bins from a plurality of frequency bins associated with a bandwidth of a channel, the first wireless transmission having a transmission power for at least one frequency bin of the first set of frequency bins that exceeds a predetermined nominal power spectral density;

means for performing, for a second duration separate from the first duration, a second wireless transmission of data via a second set of frequency bins of the plurality of frequency bins, the second set separate from the first set, the second wireless transmission having a transmission power for at least one frequency bin of the second set of frequency bins that exceeds the predetermined nominal power spectral density, wherein the second set of frequency bins is unused during the first duration and the first set of frequency bins is unused during the second duration; and

a collective power spectral density for the bandwidth averaged over the sum of the first duration and the second duration is not greater than the predetermined nominal power spectral density.